Contact assembling machine



March 8, 1966 K. R. LAGLER CONTACT ASSEMBLING MACHINE 6 Sheets-Sheet 1Filed July 17, 1964 INVENTOE LEE K. R. LAGLER CONTACT ASSEMBLING MACHINE6 Sheets-Sheet 2 March 8, 1966 Filed July 17, 1964 March 8, 1966 K. R.LAGLER 3,

CONTACT ASSEMBLING- MACHINE Filed July 17, 1964 6 Sheets$heet 5 March 8,1966 K. R. LAGLER 3,239,123

CONTACT ASSEMBLING MACHINE Filed July 17, 1964 6 Sheets-Sheet 4 March 8,1966 K. R. LAGLER 3,239,123

CONTACT ASSEMBLING MACHINE Filed July 1'7, 1964 6 Sheets-Sheet 5 2a 9|68 be 67 5| m 22 an 5! & ll Q I I 42% A/ 62 8| March 8, 1966 K. R.LAGLER 3,239,123

CONTACT ASSEMBLING MACHINE Filed July 17, 1964 6 Sheets-Sheet 6 UnitedStates Patent 3,239,123 CONTACT ASSEMBLING MACHINE Karl R. Lagler,Indianapolis, Ind., assignor to Western Electric Company Incorporated,New York, N.Y., a corporation of New York Filed July 17, 1964, Ser. No.383,359 4 Claims. (Cl. 228-18) This invention relates to a contactassembling machine, and more particularly to a machine for welding orotherwise securing tape contacts to contact springs. It is an object ofthe invention to provide an improved machine of that character.

In certain types of switches, whether in the form of relays or ofmanually operated switches, it is desired that metal tape contacts ofprecious or semi-precious metal be secured to the free ends of springs,the latter being in the form of a short length of either wire or leafspring. In the completed switch, pairs of spring contacts cooperate tomake and break a circuit, the springsof a pair being arranged parallelto each other such that the metal tape contacts engage each other eitherin the normal position of the springs or when one or both of the springsis flexed either manually or by operation of a solenoid. In one commonform of such a switch, the tape contacts are thin and elongated, inwhich case the contacts, in the completed assembly, are arranged at anangle of 90 with respect to each other such that contact therebetween isassured in spite of manufacturing tolerances.

It is another object of the invention to provide a completely automaticmachine for securing metal tape contacts to contact springs.

A further object of the invention is to provide an improved machine forassembling such contacts, which machine employs indexing apparatus toadvance metal contact tapes to positions overlying contact springs andhas provision for protection of the contact springs against damageduring retraction of the indexing apparatus.

A further object of the invention is to provide a machine for securingmetal contact tapes to both of the two cooperable contact springassemblies of a multiple contact switch, the elongated tape contactsbeing so applied to the contact springs that in the completed switch thecontacts are arranged at an angle of 90 with respect to each other.

Still another object of the invention is to provide a machine of thecharacter specified immediately above wherein no adjustment is requiredof the tape feeding angle in the securing of contacts to the contactsprings of the two cooperable contact spring assemblies.

It is another object of the invention to provide a fully automaticmachine having various of the characteristics specified above whilebeing simple in construction and efficient and reliable in operation.

In accordance with the preferred embodiment of the invention, contacttapes are advanced to positions overlying contact springs and are weldedthereto at an angle of 45 with respect to the longitudinal axes of thecontact springs. Two cooperating shear blades are operated to sever thetapes adjacent edges of the contact springs. Prior to the severing ofthe contact tapes a tape indexing head is retracted in preparation forthe advancement of the tape in the succeeding cycle of operation. Sincethe tape advancing head exerts a substantial drag on the tapes duringits retraction and since the tapes are welded to the contact springs atan angle of 45, provision is made for momentarily clamping the contactsprings firmly in position to resist bending of the springs. For thispurpose, one of the shear blades is pressed resiliently but firmlyagainst the contact springs during retraction of the tape feed head.This shear blade is arranged to be pivoted Patented Mar. 8, 1966 betweena retracted position and a tape severing position. In order to advancethe shear blade from its retracted position to a spring clampingposition, provision is made for shifting of the pivotal axis of theshear blade. The machine incorporates various features which permit thewelding of contact tape to both of the two contact spring assemblies ofa multiple contact switch at an angle of 45 with respect to thelongitudinal axes of the contact springs.

This invention, together with further objects and advantages thereof,will best be understood by reference to the following description takenin connection with the accompanying drawings, in which FIG. 1 is apartial front elevational view, partially broken away, of a machineembodying the present invention;

FIG. 2 is an enlarged view, partially broken away, of the centralportion of the apparatus shown in FIG. 1;

FIG. 3 is an enlarged, partial cross-sectional view taken along thelines 33 of FIG. 1;

FIG. 4 is an enlarged, partial cross-sectional view taken along the line4-4 of FIG. 1;

FIG. 5 is a view taken in the same plane as FIG. 4 showing tapeindexing, welding, clamping and cutting apparatus in the positionassumed immediately prior to the welding of contact tape to a contactspring;

FIG. 6 is a view similar to FIG. 5 but showing the tape being welded tothe spring contact;

FIG. 7 is a view similar to FIGS. 5 and 6 but showing the spring contactprotectively clamped during retraction of the tape indexing apparatus;

FIG. 8 is another view similar to FIGS. 5, 6 and 7 but showing theshearing of the welded tape;

FIG. 9 is a partial cross-sectional view of the machine taken along theline 9-9 of FIG. 1;

FIG. 10 is a plan view of a contact spring assembly with tape contactswelded thereto;

FIG. 11 is a similar view of a contact spring assembly with tapecontacts welded thereto, this assembly being intended for inversion andface-to-face cooperation with the assembly of FIG. 10;

FIG. 12 is an enlarged view of two pairs of cooperating spring contacts,the contact springs of the cooperative assemblies being shown in solidlines and in phantom lines, and the cooperative tape contacts of the twoassemblies being shown in contrasting form;

FIG. 13 is a view taken in the same plane as FIGS. 1 and 2 showing thecondition of shear blades when the machine is operating on the contactspring assembly of FIG. 10; and

FIG. 14 is a view similar to FIG. 13 but showing the condition of theshear blades when the machine is operating on the contact springassembly of FIG. 11.

The machine illustrated in FIGS. 19 serves to secure tape contacts to'both of two cooperative contact assemblies 20 and 30 shown in FIGS. 10and 11. These two assemblies, after the tape contacts have been securedthereto, may be brought into face-to-face relationship as part of amultiple contact switch, the elongated tape contacts of one assemblyextending at an angle of with respect to the tape contacts of the otherassembly. The completed, multiple contact switch is a manually operableswitch for use in a key set telephone, each manually operable button ofthe key set telephone serving to actuate one of the six groups of pairsof spring contacts.

The machine shown in FIG. 1 includes three welding stations identifiedas A, B, and C where lengths of metal contact tape are welded toselected contact springs of the contact spring assemblies, after whichthe tape is severed. Contacts are thus applied to the contact springassemblies at station A and B or at stations B and C,

taneously would result in interference. tional, therefore, to resort tothe time-consuming pracdepending upon which of the two assemblies isbeing fed through the machine.

Referring to FIGS. and 11 it may be seen that the two, cooperatingassemblies are not symmetrical about a centerline. The two assemblies,therefore, present different patterns, and minor adjustments of themachine must be made to weld contacts in the two different patterns.

The assembly shown in FIG. 10 includes an insulating bar 21 andseventeen contact springs identified as 22a through 2261. It will benoted that a series of holes 23 are provided in the insulating base 21for mounting purposes. These holes are used in the assembly feedingapparatus of the machine, as described below.

The spring contact assembly shown in FIG. 11, includes an insulating bar31 and seventeen contacts identified as 32a through 32g. This assemblyis also provided with mounting holes 33.

At welding station B of FIG. 1, tape contacts are welded to the firstsixteen contact springs of the assembly 20, namely the contact springs22a through 22 At welding station B, tape contacts are appliedalternatively to contact springs 320 through 32p of the assembly 30. Forthis purpose it is necessary that there be eighteen individual weldinglocations at station B. In the application of contacts to the assembly20 no welding is done at the two locations at the extreme right. In theapplication of contacts to the assembly 30 no welding occurs at the twolocations at the extreme left.

The remaining contact of each assembly is welded at station A or stationC, a contact being welded to the contact spring 22: at station A, or acontact being welded to the contact spring 32g at station C.

An important feature of the present invention is that the machine canapply contacts to both of the two assemblies 20 and 3b in such a mannerthat when the two assemblies are brought into face-to-face, cooperativerelationship, the elongated contacts of one assembly lie at an angle of90 with respect to the contacts of the other assembly such thateffective contact engagement is assured in spite of manufacturingtolerances. Furthermore, this is accomplished without adjustment of theangle of application of the tape contacts to the two assemblies.

conventionally, elongated contacts are applied to contact springs in twodifferent orientations with respect to the springs. More specifically,one contact is commonly oriented in alignment with the longitudinal axisof the spring, and the other contact is arranged to extend transverselyof the longitudinal axis of the spring. This results in the elongatedcontacts lying at an angle of 90 with respect to each other when theassemblies are brought into face-to-face, cooperative relationship. Thisconventional arrangement of contacts is normally effected through theuse of two independent machines, since the conversion of a singlemachine to apply the contacts in the two different orientations would beso extensive as to make such a machine quite impractical. Where thecontact springs are closely spaced, as in the assemblies 2% and 30, thefeeding of tape to all of the contact springs simul- It is conventice ofwelding tape to individual contact springs sequentially.

In accordance with the present invention various provisions are madewithin the machine to permit the placing of the tape contacts againstthe contact springs at an angle of with respect to the longitudinal axesof the springs. Various problems attending this arrangement, and'thesolutions thereto, are described below. With the elongated tape contactsarranged at 45 with respect to the longitudinal axes of the springs, thecontacts of both assemblies Ztl and 30 being arranged in the sameorientation, reversal or inversion of one of the assemblies andarrangement of the two assemblies in cooperative facei to-facerelationship brings the cooperating pairs of tape contacts into arelationship in which they extend at an angle of with respect to eachother, as illustrated in FIG. 12.

A conveyor is provided for advancing either of the contact springassemblies 26 or 30 to the successive welding stations A, B and C. Aportion of the conveyor can be seen in FIG. 4. A conveyor chain 41 isarranged to ride along a fixed member 42 which is secured to the frameof the machine. L-shaped lugs 43 are secured to the conveyor chain andare guided in their movement by the fixed member 42 and another fixedmember 44. A pin 43:: projects from each lug 43 and is received withinan opening 23 or 33 in the insulated support 21 or 31 of the springcontact assembly 20 or 30.

In the drawings the machine is shown applying contacts to a successionof assemblies 20. The insulated support 21 thereof may be seen in FIG.4, the main length of the contacts 22 extending downward therefrom. Itwill be noted that the insulating support 21 is confined by the lugs 43and the fixed members 42 and 44 such that its movement is limited to adirection longitudinal of itself.

Since the drive apparatus for the conveyor chain 41 does not of itselfconstitute a feature of this invention, and since it may be of anyconventional form, it is not shown herein. It will, of course, beappreciated that indexing movement of the chain 41 should be insynchronism with other operating parts of the machine.

With successive spring contact assemblies 20 arranged at the threewelding stations A, B and C, contact tape 51 is advanced toward thewelding stations. In FIG. 4 a cam 52 is shown controlling a cam follower53 mounted on a lever 54. This lever is secured to a shaft 55 which canbe seen also in FIG. 1.

At each end of the shaft 55 there is a tongue 56 which has an aperturefor receiving a pin 57, the pin being rotatable within the tongue butfixedly positioned with respect thereto by collars 5%.

The free ends of the pins 57 are pivotally connected to respectiveadjustable links 59 through pins 57a, and the upper ends of these linksare pivotally connected to a tape feeding head 6% through pins 59a. Itmay now be seen that as the cam 52 rocks the lever 54, the links 59cause raising and lowering of the tape feeding head 60. Since the pins57 are rotatable within the tongues 56 at the ends of the shaft 55, andsince the links 59 are pivotally connected to the tape feeding head 60,the tape feeding head at is free to swing to the right and left asviewed in FIG. 1.

A pair of guide rods 61 (see FIG. 1) are set in a guide member 62 (bestseen in FIG. 4) and are received in openings provided in the tapefeeding head 60 for that purpose. Accordingly, as the tape feeding headis raised, through operation of the cam 52, it is guided to the right inFIG. 1 by the guide rods 61, such that it rises at an angle of 45.Through this arrangement vertical movement of the tape feed drive isconverted to movement of the tape feed head at an angle of 45 withrespect to the vertical. This is desirable as it permits the use ofhorizontal shafts for the driving of all cams.

The guide member 62 not only supports the guide rods 61 but also definesa slot 62a which slidably receives portions of the tape feeding head 60,as shown in FIG. 4. The guide member 62 is pivotally mounted on theframe of the machine through pins 63 (see FIG. 1) which areapproximately concentric with the pivotal connections of the links 59with the pins 57. It will be appreciated that these pivotableconnections are not truly concentric since the pins 63 are secured tothe frame of the machine whereas the pivotable connections between thepins 57 and the links 59 move a short distance vertically in response torotation of the cam 52. It will also be appreciated that preciseconcentricity is not required. Control of pivotal movement of the guidemember 62 and, hence, of the tape feeding head 60 is described below.

The tape feeding head 60 is shown also in FIG. 3 wherein it may be seento carry a plurality of pawls 64 biased by springs 65. Each of the pawls64 serves as a one-way feed device for a strand of contact tape 51. Morespecifically, as the tape feeding head 60 rises it advances the tape 51therewith, and as the tape feeding head is lowered, the tape 51 isrelatively free to remain in its advanced position. It will beappreciated that there is a pawl 64 for each strand of contact tape. Thetape feeding head also carries a welding head 66 including a pluralityof electrodes 67 provided with leads 68.

As the tape feeding head rises it is necessary that the tapes bepositioned slightly in front of the spring contacts, to the left asviewed in FIGS. 3 and 4, in order that the ends of the tapes may notstrike the ends of the spring contacts. After the tape feeding head hasbeen fully raised it is desirable that it be swung to the right in FIG.4 such that the ends of the tapes may be brought into contact with thecontact springs. Still further, since the welding head 66 is secured tothe tape feeding head 60, further rightward movement of the tape feedinghead is desired in order to bring the welding electrodes 67 into play.It is for these reasons that the guide member 62 is made pivotable aboutthe pins 63 of FIG. 1.

Each end of the guide member 62 is biased toward the right, as viewed inFIG. 4, by a spring 70 acting through a lever 71 pivoted at 72, and alink 73 which is pivotally connected to the lever 71 and to the guidemember 62.

Leftward pivotal movement of the guide member 62, against the biasing ofthe springs 71, is effected by the cam 52 acting through a cam follower75 and a lever 76 which is pivoted at 77. The lever 76 carries a rod 78,and the ends of the rod 78 are connected to plungers 79 (only one ofwhich is shown) slidable in sleeves 80. A bar 81 is connected to theforward end of each of the plungers 79, and this bar carries a pluralityof pins 82 which bear against the right-hand edge of the tape feedinghead 60.

It will be apparent that as the cam 52 rocks the lever 76 to the left inFIG. 4 the pins 82 force the tape feeding head to the left against thebias of the springs 70. When the lever 76 is rocked to the right itwithdraws the pins 82 and allows the springs 70 to advance the tapefeeding head 60 to the right.

Initial rightward movement of the tape feeding head 60 places the endsof the contact tapes against the contact springs and continued movementbrings the electrodes 67 into contact with the tapes. The contactsprings are pressed against a stationary electrode 83 such that uponapplication of electric power current flows from the movable electrodes67 through the contact tapes and the corresponding contact springs tothe common stationary electrode 83. The current is sufficient to weldthe contact tapes to the corresponding contact springs.

Upon completion of the welding of the contacts, the tape feeding head 60is pivoted to the left and lowered by the cam 52, the pawls 64 slidingalong the respective tapes which remain in their advanced positions.Shear blades are then operated to sever the tapes adjacent edges of thespring contacts.

Since the pawls 64 exert a substantial drag. on the respective tapes asthe tape feeding head is lowered and since the drag pulls on the contactsprings at an angle of 45, it is necessary that the contact springs befirmly clamped against the fixed electrode 83 during retraction of thetape feeding head.

In accordance with one feature of the present invention this clamping iseffected through use of one of the shear blades 91. This upper shearblade is, therefore, arranged to move from its retracted position (shownin solid lines in FIG. 4) to two different operating positions. One ofthese is its tape shearing position (shown in phantom lines in FIG. 4)and the other is its clamping position.

The upper shear blade is secured to a pair of arms 91a which are in turnsecured to a shaft 92. The shaft 92 is caused to rotate through a smallangle by rotation of a cam 93. The cam has a track which cooperates witha cam follower 94, the cam follower being mounted at one end of an arm95. The other end of the arm 95 is freely rotatable about the shaft 92but has a lug 96 which supports a spring 97. This spring bears against alug 98' on an arm 99 which is secured to the shaft 92. Another lug 100on the arm 99 limits counterclockwise rotation of the arm 99 withrespect to the arm 95.

It will now be apparent that leftward movement of the arm 95 resilientlyurges counterclockwise rotation of the arm 99, the shaft 92, the arms91a and the upper shear blade 91. This brings the shear blade 91 to itstape shearing position, which is shown more clearly in FIG. 8.

As will be apparent upon reference to FIG. 4, the upper shear blade 91cannot be brought to tape severing position to hold the contact springsagainst displacement by the retraction of the tape feeding head 60 sincethe shear blade 91 in such a position would conflict with the movablewelding electrodes 67. In order to employ the upper shear blade 91 forthis purpose another movement is provided such that the blade may beclamped against the contact springs in a position substantially aboveits cutting position.

For this purpose, the shaft 92 is movably supported by and rotatablewith respect to a pair of arms 101, as shown in FIG. 9. These arms aresecured to shafts 102. Also secured to each shaft 102 is another arm 103carrying a lug 104. A pair of cams 105 cooperates with cam followers 106carried at the free ends of corresponding arms 107 which are freelypivoted on the shafts 102. Each of the arms 107 has a lug 108, and acompression spring 109 is arranged between the lugs 104 and 108. Anotherlug 110 on each of the arms 103 limits clockwise movement of the arm 107with respect to the arm 103 as viewed in FIG. 9.

When the cams 105 move the cam followers 106 forward (to the left inFIG. 9) the arms 107, acting through the springs 109 swing the arms 104forward. This swings the arms 101 rearward such that the shaft 92 isdisplaced toward the rear and downward to the position illustrated inphantom lines in FIG. 9.

Referring now to FIG. 4, it may be seen that this rearward displacementof the shaft 92 draws the upper shear blade 91 against the contactsprings 22 of the contact spring assembly 20 as illustrated in FIG. 7.By virtue of the resilience which is provided by the spring 109 (seeFIG. 9) the cutter blade 91 may be pressed tightly against the springcontacts without the necessity of severe manufacturing tolerances.

Upon completion of the retraction of the tape feeding head 60, furtherrotation of the cam 105 releases the clamping action of the upper shearblade 91 and returns the shear blade 91 to the position shown in FIGS. 5and 6 and illustrated by solid lines in FIG. 4.

The upper shear blade 91 may then be moved to sever the contact tapes.Rotation of the cam 93 of FIG. 4 lowers the shear blade 91 to theposition shown in FIG. 8 and illustrated in phantom lines in FIG. 1 inthe manner described above. The cam 52 of FIG. 4 then advances theplungers 79 and the bar 81. As described above, this swings the tapefeeding head 60 and the welding head 66 forward. The bar 81 also carriesa lower shear blade 111 which cooperates with the upper cutter blade 91to sever the contact tapes immediately adjacent edges of the contactsprings, also shown in FIG. 8.

Another problem attending the application of contact tape to the springsat an angle of 45 with respect to the longitudinal axes of the springsarises from the fact that the rolls of tape are preferably rotatableabout horizontal axes. With this preferred arrangement, the tapes reachthe machine traveling vertically and must be turned through an angle of45. Furthermore, the tape, which is commonly substantially wider than itis thick (.03 8" by .019" in one application) must, in effect, be turnededgewise. This tends to produce substantial binding of the tape.

In the illustrated embodiment of the invention effective edgewiseturning of the tape is accomplished without actual edgewise bending ofthe tape. As the tapes approach the machine from below they pass throughsuitable grooves in a fixed block 115 seen in FIG. 1. Above this blockand spaced from it is a bar 6.2a which forms a part of the guide 62. Thebar 62a also has grooves for receiving the individual tapes.

Between the block 115 and the bar 62a the tapes are suspended freely.Accordingly, edgewise turning of the tapes induces twisting of the tapesthrough an angle of approximately 90 and bending of the tapes in thenormal direction, followed by twisting of the tapes back to theiroriginal planes. Free suspension of the tapes thus permits edgewiseturning of the tapes without the binding which would necessarilyaccompany edgewise bending of the tapes.

The apparatus has been described to this point as adjusted to handle thespring contact assembly 21} of FIG. 10. Certain minor adjustments arerequired in order to adapt the machine to handle the assembly 31) ofFIG. 11.

One adjustment which is required is the activating of the two weldingheads at the extreme right at station B and the deactuating of the twowelding heads at the extreme left of station B. Also, the welding headat station C must be activated and the welding head at station A must bedeactuated. This adjustment can readily be accomplished through theoperation of switches. Since the control circuitry does not of itselfconstitute a feature of the present invention and may be conventional inform it is not shown or described in detail herein.

No adjustment of the tape feed mechanism is required. When the tapefeeding head 60 retracts, those tapes whose free ends have not beenwelded to a contact spring are drawn downward with the head, and arelater advanced to their original positions. These tapes will, therefore,merely be shifted back and forth rather than being indexed. As explainedabove, no change is required in the angle of the tapes relative to theaxes of the contact springs.

Relative to the cutting of the tape subsequent to welding, provision ismade for shifting of the upper shear blade 91. Referring to FIGS. 13 and14, it may be seen that the upper shear blade 91 is in its rightwardposition when the machine is handling the assemblies 20, and in itsleftward position when handling the assemblies 31 With the upper shearblade in its rightward position, as shown in FIG. 13, provision is madefor severing tape at station A after it has been welded to springcontact 226 At station C the common electrode or backup plate 83 isnotched to permit rearward movement of the contact spring 22a such thatthe upward protrusion at the righthand end of the lower shear blade 111does not damage this contact spring.

With the upper shear blade H moved to its leftward position as shown inFIG. 14, provision is made at station C for the severing of tape whichhas been welded to the contact spring 32: More specifically, the upwardprotrusion at the righthand end of the lower shear blade 111 cooperateswith a downwardly extending righthand portion of the upper shear blade91. At station A, damage to the contact springs 32a and 32b is avoidedby the removal of a portion 111a of the lower shear blade 111.

Provision for the lateral shifting of the upper shear blade 91 is shownin part in FIG. 4. The righthand ends of the arms 91a are secured to theshaft 92 only indirectly, the arms having circular openings which freelyreceive the shaft. The arms 91a are releasably secured to the shaft 92through use of a clamp 9111. Each of the arms 91a has a groove in itsupper surfaceand a groove 8 in its lower surface for receiving the two'arms of the clamp 9117.

At two points along the length of the shaft 92 there are flat spotswhose axial and radial dimensions are such as to receive the arms of theclamp 91 snugly. When the upper shear blade 91 is in one of itsoperating positions the clamp 91b may be inserted in the grooves in oneof the arms 91a and engage one pair of flat spots on the shaft 92. Ascrew 910 is inserted through the clamp 91b and into a threaded openingin the shaft 92 to hold the clamp in place. Since the clamp engages fiatspots on the shaft 92 it is non-rotatable with respect thereto, andsince the arms of the clamp 9112 are arranged in the upper and lowergrooves in one of the arms 91a, the upper shear blade 91 isnon-rotatable with respect to both the clamp 91!: and the shaft 92.

When the upper shear blade 91 is in its other operating position, thearms of the clamp 91!) may be inserted in the grooves in the other oneof the arms 91a and engage the other pair of flat spots on the shaft 92.Since the manner of securing the arms 91a of the upper shear blade 91 tothe shaft 92 does not of itself constitute a feature of the presentinvention, and since the apparatus for this purpose may be of variousforms obvious to those skilled in the art, it is not shown or describedin detail herein.

While operation of the apparatus is believed to be apparent from theabove description, a brief resum of operation is given below, primarilyin the interest of clarifying the sequence.

Let it be assumed that the machine is in adjustment for the handling ofthe contact spring assemblies 21) of FIG. 10 and that an assembly hasbeen advanced to each of the stations A, B and C. Rotation of the cam 52of FIG. 4, acting through the cam follower 53, raises the tape feedinghead and the welding head 66, the tape feeding head guide 62 beingtipped forward, or to the left in FIG. 4. This advances the ends of thetapes to positions overlying the contact springs 22a through 22p atstation B and the contact spring 22g of the trailing assembly at stationA. The tape feeding head 60 and the shear blades 91 and 111 are then inthe position illustrated in FIG. 5.

The cam 52 then operates through the cam follower to withdraw the bar 81such that the springs 711 may force the ends of the tapes against thecontact springs and force the welding electrodes against the tapes. Thiscondition is illustrated in FIG. 6. The electrodes are then electricallyactuated to effect the welding of the tapes to the contact springs.Electrical actuation of the electrodes may, of course, be accomplishedautomatically by obvious means.

The cams of FIG. 9 then draw the shaft 92 to the right such that theupper shear blade 91 is brought into firm engagement with portions ofthe contact springs immediately above the tapes.

Further rotation of the cam 52 of FIG. 4 lowers the tape feed head, thepawls 64 thereof sliding along the tapes. Bending of the contact springsto which the tapes have just been welded is avoided by the clamping ofthe contact springs against the commonelectrode 83 by the upper shearblade 91. This condition is illustrated in FIG. 7.

Further rotation of the cams 105 of FIG. 9 moves the upper shear blade91 forward to its normal, retracted position, shown in solid lines inFIG. 4.

At this time, the cam 93 of FIG. 4 pivots the upper shear blade aboutthe shaft 92 such that the upper shear blade is lowered to its cuttingposition. The cam 52 of FIG. 4, operating through the cam follower 75,then advances the bar 81 and the lower shear blade 111 to sever thetapes in the manner illustrated in FIG. 8. This also tilts the tape feedheads 6t) to the left, as viewed in FIG. 4, in readiness for the nextcycle of operation. Prior to the next cycle the conveyor chain 41indexes all of the 9 contact spring assemblies 20 one station to theright as viewed in FIG. 1.

Apparatus has now been described for welding elongated bits of contacttape to the contact springs of the two contact spring assemblies of amultiple contact switch, the operation being fully automatic. Themachine is arranged to permit adjustment such that either of the twocooperative contact spring assemblies of the complete multiple contactswitch can be handled, even though the pattern of contact springs isnon-symmetrical about a centerline. The machine is so arranged that noadjustment is required in the angle of application of the elongated tapecontacts to the contact springs of the two assemblies in order that theelongated contacts may lie at an angle of 90 with respect to each otherwhen the two contact assemblies are brought into face-to-facecooperative relationship. This effect is accomplished through thesecuring of the tape contacts to the contact springs at an angle of 45with respect to the longitudinal axis of the contact springs and throughproviding the machine with various features which permit suchapplication of the tapes to the springs.

While one embodiment of the invention has been disclosed, manymodifications will be apparent, and it is intended that the invention beinterpreted as including all modifications which fall within the truespirit and scope of the invention.

What is claimed is:

1. In a machine for applying metal tape contacts to contact springs:

alternately advancing and retracting indexing means for advancing oneend of a metal contact tape to a position overlying a contact spring;

means for securing the end of the contact tape to the contact spring;

first and second cutter blades; and

blade actuating means for clamping one of said blades against thecontact spring during retraction of said indexing means to preventbending of the contact spring, and for moving said one blade to severthe tape in cooperation with the other of said blades followingretraction of said indexing means.

2. Apparatus as specified in claim 1, wherein said blade actuating meansincludes means for pivoting said one blade about a shaft between aretracted position and a tape cutting position, and means for moving theshaft to advance said one blade from its retracted position to a tapeclamping position.

3. Apparatus for applying lengths of metal contact tape to contactsprings of two cooperable contact spring assemblies of a multiplecontact switch, which comprises:

means for advancing successive contact spring assemblies to a weldingstation;

springs;

means for severing the contact tapes adjacent the edges of the contactsprings; and

indexing means for advancing metal contact tapes toward the weldingstation prior to operation of said welding means and for arranging thefree ends of the tapes in positions overlying the contact springs at anangle of 45 with respect to the length of the contact springs wherebycooperable contacts of the completed assemblies extend at an angle ofwith respect to each other when the two assemblies are arranged incooperative, face-to-face relationship.

4. Apparatus for applying a length of metal contact tape to contactsprings of two cooperable contact spring assemblies of a multiplecontact switch, which comprises:

means for advancing successive contact spring assemblies to a weldingstation; alternately advancing and retracting indexing means foradvancing metal contact tapes toward the welding station and forarranging the free end of each tape in a position overlying a contactspring;

means for welding the contact tapes to the contact spring;

first and second cutter blades; and

blade actuating means for clamping one of said blades against thecontact springs during retraction of said indexing means to preventbending of the contact springs, and for moving said one blade to severthe tape in cooperation with the other of said blades followingretraction of said indexing means;

said indexing means arranging the conta-ct tapes at an angle of 45 withrespect to the length of the spring contacts whereby cooperable contactsextend at an angle of 90 with respect to each other when the twoassemblies are arranged in cooperative, face-to-face relationship.

References Cited by the Examiner UNITED STATES PATENTS 2,307,579 1/1943Fluke 228-18 2,388,754 11/1945 Martindell 228-18 FOREIGN PATENTS 523,4557/ 1940 Great Britain.

References Cited by the Applicant UNITED STATES PATENTS 799,680 9/1905Sloan 83-215 2,039,108 4/1936 Owens 179-1003 2,236,192 3/1941 Hazelton83-374 2,329,549 9/ 1943 Maurer 83-456 2,636,423 4/1953 Cunningham 93-372,873,448 2/1959 Berg 1-177 3,009,200 11/ 1961 Voigt 18-14 WHITMORE A.WILTZ, Primary Examiner.

1. IN A MACHINE FOR APPLYING METAL TAPE CONTACTS TO CONTACT SPRINGS;ALTERNATELY ADVANCING AND RETRACTING INDEXING MEANS FOR ADVANCING ONEEND OF A METAL CONTACT TAPE TO A POSITION OVERLYING A CONTACT SPRING;MEANS FOR SECURING THE END OF THE CONTACT TAPE TO THE CONTACT SPRING;FIRST AND SECOND CUTTER BLADES; AND BLADE ACTUATING MEANS FOR CLAMPINGONE OF SAID BLADES AGAINST THE CONTACT SPRING DURING RETRACTION OF SAIDINDEXING MEANS TO PREVENT BENDING OF THE CONTACT SPRING, AND FOR MOVINGSAID ONE BLADE TO SEVER THE TAPE IN COOPERATION WITH THE OTHER OF SAIDBLADES FOLLOWING RETRACTION OF SAID INDEXING MEANS.